The videos shows chaotic scenes as victims are rushed to hospital for treatment in the village of Talmenes in Idlib province. Many are coughing and retching, while others have donned facemasks or gas masks.

In a hospital clinic, men and women writhe around on beds awaiting treatment while other victims are carried in to receive medical help.

The footage also shows what is claimed to be debris from the so-called barrel bombs used in the attack, with the corpses of dead livestock strewn nearby.